Low-invasion operations carried out by inserting a device for diagnosis or treatment, such as a catheter, into a blood vessel or some other tissue are known and performed on a quite often basis. For example, to treat a constriction of the coronary artery of the heart, it is necessary to insert a device such as a catheter into a blood vessel in order to perform therapeutic treatment on the constriction.
This insertion of an instrument such as a catheter into a blood vessel is normally performed through a puncture formed by dissecting or puncturing the femoral region. After the therapeutic treatment is completed, it is necessary to perform a staunching operation to stop the bleeding through the puncture. However, since the blood pressure upon bleeding (bleeding blood pressure) from the femoral artery is relatively high, it is oftentimes necessary for a person involved in the medical procedure to use a finger of their hand to press down on the site for a relatively long period of time.
In recent years, to perform the stoppage of bleeding more readily and with greater certainty, a variety of devices have been proposed for insertion through an opening penetrating a tissue membrane (an opening on a wall of living body cavity) to close the opening (e.g., the opening in the blood vessel). The device disclosed in Japanese Patent No. 3133059, (corresponding to U.S. Pat. No. 5,593,422) is an example.
Japanese Patent No. 3133059 discloses a device in which a closing member with a thread attached thereto is disposed in a blood vessel, a ring (locking member) is moved along the thread, and the ring locks the thread outside the blood vessel to close up the opening formed in the wall of the blood vessel.
In this disclosed device, the closing member is secured to the wall of the blood vessel by fixing the ring to the thread.
However, with the device just mentioned, since the fixing operation involving the fixing of the ring to the thread must be performed within subcutaneous tissues, the fixing operation is difficult to carry out. Besides, after the ring is fixed to the thread, it is necessary to cut the thread within the subcutaneous tissues. Therefore, labor, time and skill are required to close up the opening formed in the wall of the blood vessel.
Further, since the outside diameter of the ring needs to be dimensioned so that the ring can be inserted into the opening, the ring must necessarily be relatively small in size, and there is the possibility that the ring may drop into the blood vessel through the opening formed in the wall of the blood vessel.